The Pentagon Paradox
The Development of the F-18 Hornet
by James P. Stevenson
Few weapons systems have grown in cost over the last decades as fighter aircraft. During the Second World War, a $70,000 Sherman tank cost more than a $54,000 Mustang fighter. Today, you can buy ten M1A2 Abrams tanks for the cost of a single F-35 Joint Strike Fighter. Has performance improvement been commensurate with the increased cost? This is a complex question, for which you have to read this book, but the short answer is "no". Stevenson calls this the "Pentagon Paradox".
In the Second World War, the US Army Air Force shot down 1.29 enemy aircraft for every one of its own aircraft shot down. In Korea, this ratio rose to 6.2:1 before - as anyone who has seen the movie Top Gun knows - with more sophisticated aircraft it fell to 2.4:1 in Vietnam and the US Navy introduced Top Gun schooling was introduced to bring it back up again.
In the early 1970s, aerial tacticians like Pierre Sprey and John Boyd looked at the new fighters of the day like the F-14 Tomcat and F-15 Eagle and were not impressed. These fighters were designed around the requirements of long range over-the-horizon missiles like the Sparrow and Phoenix. These required large radars which gave the aircraft a large cross section. In turn this made the aircraft larger and required a bigger engine. However the tacticians questioned the value of the long range missile.
In Vietnam, the rules of engagement prohibited firing missiles at targets that had not been visually confirmed. As a result, some 40% of kills were achieved with cannon. Incredibly, the cannon had been omitted from the original design of the F-4 Phantom as being obsolete. Between 1965 and 1968 the US Air Force fired 224 Sparrow missiles for 20 kills (8.9%). The smaller infra-red seeking Sidewinder, which cost one third as much, scored 28 kills from 175 missiles (16.0%).
Yet in late 1969, in support of the F-15 project, Lieutenant Colonel Larry Welch predicted a proposed missile called the AIM-82 would give it a kill ratio of 955:1! Even the brass were aghast. If the bean counters got a hold of this, they might take the Air Force at its word and provide it with just six F-15 aircraft, reasoning that this should be enough to shoot down the entire Soviet Air Force!
The reformers were no less sceptical about the value of expensive radars which give away the aircraft's position to and high speeds. The F-15, for example, can indeed fly at Mach 2.5, as specified in the contract. But it cannot do so while carrying weapons or without engaging a special feature to increase the turbine pressure. This burns up fuel very rapidly and incidentally requires an engine overhaul. Yet all this complexity adds up to increased hours in the workshop and less time for the pilots in the air. This is why the much simpler A-10 Warthog was able to achieve much higher sortie rates in Iraq.
This sort of thing spurred determined and intrepid, albeit clandestine and unofficial, efforts within both the US Air Force and the US Navy to develop a lightweight fighter more suitable to aerial combat. The navy project was soon canned but ironically it spurred the air force to develop their own version, lest Congress or the Department of Defence force the navy's lightweight fighter upon it, as had happened with the F-4 Phantom and A-7 Corsair.
The result was a competitive flyoff between two prototypes, the General Dynamics (now Lockheed-Martin) YF-16 and the Northrop YF-17, with the former being selected as the eventual winner. Stevenson chronicles how the navy then ran scared from having an air force aircraft foisted upon it and eventually chose to adopt the YF-17, which was navalised as the F-18 Hornet. The Navy insisted on the Sparrow missile, the desirability of two engines and a host of trivial "carrier capable" performance metrics that it had waived for other aircraft and ultimately for the F-18 too.
The book then follows the development of this aircraft as it, like the F-16, slowly became heavier and more sophisticated and then the war in Iraq, where the F-18 had a kill ratio of 2:1, with both of its air-to-air kills being with Sidewinder missiles.
In the final analysis, is the F-18 Hornet good aircraft ? This is a complex question, for which you have to read this book.